MathSciDoc: An Archive for Mathematician ∫

@inproceedings{h.1977an,
  title={An elementary method in the study of nonnegative curvature},
  author={H. Wu},
  url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203248034910251},
  booktitle={Acta Mathematica},
  volume={142},
  number={1},
  pages={57-78},
  year={1977},
}